CRF in the MS disrupted spatial memory and males were more sensitive to this effect, but recognition memory was unaffected. A) In the object location task, the 100 ng dose of CRF in the MS reduced the ratio of time spent with the displaced compared to the familiar object in both sexes, but the 3 ng dose only reduced this ratio in males when compared to aCSF-treated controls. B) In the object recognition task, CRF in the MS did not alter the ratio of time spent with the novel, relative to the familiar object. The dashed line marks a ratio of 1, when an equal amount of time is spent with both objects, indicative of no memory. Data are represented as mean ± SEM, asterisks indicate (p < .05) from same sex aCSF-treated controls.